Copyright © 2007 Open Geospatial Consortium, Inc. All Rights Reserved.
27
Figure 6 — CV_DiscretePointCoverage
6.2.2 Inherited associations and operations
CV_DiscretePointCoverage Figure 6 inherits the association CoverageFunction and the operations locate, find,
and list
from CV_DiscreteCoverage
5.7, with
the restriction
that the
associated CV_GeometryValuePairs and those returned by the operations shall be limited to CV_PointValuePairs.
6.3 CV_PointValuePair
CV_PointValuePair is the subtype of CV_GeometryValuePair that has a GM_Point as the value of its geometry attribute.
6.4 CV_DiscreteGridPointCoverage
6.4.1 General
The domain of a CV_DiscreteGridPointCoverage Figure 7 is a set of CV_GridPoints 8.5 that are associated with records of feature attribute values through a CV_GridValuesMatrix 8.14.
6.4.2 Inherited associations and operations
CV_DiscreteGridPointCoverage Figure 7 inherits the association CoverageFunction and the operations locate, find, and list, from CV_DiscreteCoverage, with the restriction that the associated
CV_GeometryValuePairs and those returned by the operations shall be limited to CV_GridPointValuePairs. The association CoverageFunction is shown as derived in this case because the elements may be generated
from the CV_GridValuesMatrix through the association PointFunction. The inherited operations evaluate and evaluateInverse use CV_GridValuesMatrix to assign values to the CV_GeometryValuePairs.
Copyright © 2007 Open Geospatial Consortium, Inc. All Rights Reserved.
28
Figure 7 — CV_DiscreteGridPointCoverage
6.4.3 point
The operation point g: CV_GridCoordinates: CV_GridPointValuePair shall accept a grid coordinate as input and use data from the associated CV_GridValuesMatrix to construct and return the CV_GridPointValuePair
associated with that grid position.
6.4.4 PointFunction
The association PointFunction shall link the CV_DiscreteGridPointCoverage to the CV_GridValuesMatrix for which it is an evaluator.
6.5 CV_GridPointValuePair
CV_GridPointValuePair is the subtype of CV_GeometryValuePair that has a GM_GridPoint as the value of its geometry attribute.
6.6 CV_DiscreteCurveCoverage
6.6.1 General
A discrete curve coverage is characterized by a finite spatial domain consisting of curves. Often the curves represent features such as roads, railroads or streams. They may be elements of a network.
EXAMPLE A coverage that assigns a route number, a name, a pavement width and a pavement material type to
each segment of a road system.